McAllister, who largely self-funded his campaign, beat establishment candidate Neil Riser, a state senator, in Saturday's runoff election for the vacant 5th District seat. He will complete the unfinished term of former U.S. Rep. Rodney Alexander.

Some critics suggested that Alexander's sudden resignation and the support of Riser by Alexander and by Gov. Bobby Jindal amounted to an "anointment" as Alexander's heir.

Voters saw things differently.

Both McAllister and Riser are Republicans, but McAllister ran as an outsider, capitalizing on voter frustration with politicians and Congress.

After finishing second in a crowded primary field, McAllister, a businessman from Ouachita Parish, blitzed by Riser on Saturday. With more than 90 percent of the votes counted, McAllister held an advantage of 18 points.

The 5th District reaches from northeastern Louisiana into parts of Washington and Tangipahoa parishes. It is considered to be one of the poorest districts in the nation.

Though registered Democrats outnumber Republicans, the district is viewed as a GOP lock because of a conservative shift that has taken place in recent decades.

McAllister will serve the final year of Alexander's term and is likely to run for reelection in 2014.

The biggest disagreement between McAllister and Riser involved President Barack Obama's signature health care law. McAllister said it was unrealistic to try to throw out the plan at this point, though he opposes it, while Riser took a firmer position seeking a repeal.

Click here for the results to all of the elections in southeast Louisiana.